METHODS: The antimicrobial activity was tested against the planktonic S. aureus cells using the microdilution broth assay, while the antibiofilm activity were evaluated using the crystal violet and resazurin assays. The cytotoxicity of the SBDs was assessed on MRC5 (normal lung tissue), using the MTT assay.
RESULTS: The individual SBDs showed significant reduction of biomass and metabolic activity in both S. aureus strains. Combinations of the SBDs with OXA and VAN were mainly additive against the planktonic cells and cells in the biofilm. Both the compounds showed moderate toxicity against the MRC5 cell line. The selectivity index suggested that the compounds were more cytotoxic to S. aureus than the normal cells.
CONCLUSION: Both the SBD compounds demonstrated promising antimicrobial and antibiofilm activities and have the potential to be further developed as an antimicrobial agent against infections caused by MRSA.
MATERIALS & METHODS: The Schiff base ligand was synthesized by refluxing isatin and thiosemicarbazide for 3 hours. Complexes 2 and 3 were formed and characterized using elemental analysis, molar conductivity, IR, NMR, and UV-Visible spectroscopy. The geometry of complex 3 was determined via X-ray diffraction. Theoretical calculations were conducted using DFT with the hybrid GEN B3LYP method. Molecular docking was performed to assess binding energies with EGFR, and anticancer activity was evaluated against the A549 cell line.
RESULTS: Characterization confirmed successful synthesis of the compounds. Zinc complexation led to notable spectral shifts, and X-ray diffraction revealed complex 3 adopted a distorted tetrahedral geometry. DFT analysis highlighted complex 2 with the lowest energy gap (0.331 eV). Docking results showed strong EGFR binding energies (-5.70, -5.54, and -7.30 kcal/mol). Complex 2 demonstrated the highest anticancer efficacy with a cell viability of 1.35% after 48 h.
CONCLUSIONS: Complex 2 exhibits significant anticancer potential and warrants further investigation as a therapeutic agent.
OBJECTIVE: The present study was aimed to synthesize and evaluate antimicrobial and anticancer activities of Schiff bases of 2-mercaptobenzimidazole.
METHODS: The Schiff bases of 2-mercaptobenzimidazole were synthesized from 4-(2-(1H-benzo[d]- imidazol-2-ylthio)acetamido)benzohydrazide. The synthesized compounds were evaluated for antimicrobial and anticancer activities by tube dilution method and Sulforhodamine-B (SRB) assay, respectively.
RESULTS: Compounds 8 (MICpa, an = 2.41, 1.20 µM/ml), 10 (MICse, sa = 2.50 µM/ml), 20 (MICec = 2.34 µM/ml) and 25 (MICca = 1.46 µM/ml) showed significant antimicrobial activity against tested bacterial and fungal strains and compounds 20 (IC50 = 8 µg/ml) and 23 (IC50 = 7 µg/ml) exhibited significant anticancer activity.
CONCLUSION: In general, the synthesized derivatives exhibited moderate antimicrobial and anticancer activities. Compounds 8 and 25 having high antifungal potential among the synthesized compounds may be taken as lead molecules for the development of novel antifungal agents.